Your stomach is a very complex organ that has a muscle layer, it has an epithelial layer which is the interface with food that comes in, and it also has a nervous system, so does the heart.

你的胃是一个非常复杂的器官,它拥有一个肌肉层,有一个与摄入的食物,相接触的表皮层,也有一套神经系统,心脏也有

耶鲁公开课 - 生物医学工程探索课程节选